An application device is known from the published EP 1 138 397 A2, for example. This published document proposes a device for dispensing a pasty two-component mixture, the device being provided with a supply container having at least two chambers for each of the pasty components of the mixture, wherein the supply container has an outlet port for each chamber; a mixer unit having a tubular mixer housing with a mixer element arranged therein, wherein the mixer housing includes a coupling end, which can be coupled to the supply container and has two inlet ports, and two channels for the pasty components of the mixture leading to the mixer element, and further includes, at the opposite end, an outlet opening for the mixture, wherein the inlet ports can be inserted into the outlet ports, or vice versa, and a holding sleeve for the coupling end of the mixer housing, the sleeve being mounted rotatably on the supply container, wherein the holding sleeve surrounds the two outlet ports and has a cut-out, the shape of which at least in some sections is substantially identical to the cross-sectional shape of the coupling end of the mixer housing, wherein the holding sleeve can be rotated between a receiving rotational position, in which the cut-out is oriented in keeping with the orientation of the coupling end of the mixer housing when the inlet ports are connected to the outlet ports of the supply container, and a locking rotational position, in which at least a part of the cut-out edge of the holding sleeve extends over and into parts of the coupling end of the mixer housing.
This known application device can be difficult to handle, for example when replenishing the substance components and when using the device with only some of the filled-in substance components.